IP Library › Granted Patent US 12,562,286
Granted Patent B2
US 12,562,286 · App. 18/119,978 · Granted Feb 24, 2026

System and method for stellarator neutron source

Inventor: David Gates (Princeton, NJ)
Assignee: THE TRUSTEES OF PRINCETON UNIVERSITY
G21B1/055G21G4/02H05H3/06
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Quick Facts
Patent No.
US 12,562,286
App. No.
18/119,978
Granted
Feb 24, 2026
Kind
B2
Abstract

The present disclosure is directed to systems for generating neutrons, the systems including a stellarator optimized for fast particle finement. In some embodiments, the stellarator optimized for fast particle confinement is selected from a quasi-axisymmetric stellarator, a quasi-symmetric stellarator, a quasi-isodynamic stellarator, or a quasi-omnigenous stellarator. The present disclosure is also directed to methods of generating neutrons using the systems of the present disclosure and, in particular, systems incorporating a stellarator optimized for fast particle confinement.

Claims (15)

1 . A system comprising: (a) a stellarator adapted to confine a plasma within a first volume, wherein the stellarator includes (i) a casing defining the first volume; and (ii) a blanket defining a second volume, wherein the blanket envelops the casing and thereby radially circumscribes the plasma confined by the stellarator; (b) at least a first negative ion-based neutral beam injector in communication with the stellarator configured to introduce high energy neutral atoms into the plasma confined by the stellarator in a first toroidal direction along a plasma axis; (c) at least a second negative ion-based neutral beam injector in communication with the stellarator configured to introduce high energy neutral atoms into the plasma confined by the stellarator in a second toroidal direction along the plasma axis, wherein the first and second toroidal directions are opposite toroidal directions; and (d) an electron heater in communication with the stellarator, wherein the electron heater is adapted to heat electrons in the plasma; wherein the stellarator comprises (a) a plurality of planar shaping coils, wherein an array comprising the plurality of planar shaping coils encircles the plasma axis, but where any individual planar shaping coil of the plurality of planar shaping coils does not encircle the plasma axis; and (b) a plurality of planar encircling coils, wherein each individual planar encircling coil of the plurality of encircling coils encircles the plasma axis; and wherein any planar shaping coil of the plurality of planar shaping coils does not interlock with any planar encircling coil of the plurality of planar encircling coils.

2 . The system of claim 1 , wherein the stellarator is a quasi-helically symmetric stellarator, a quasi-isodynamic stellarator, or a quasi-omnigenous stellarator.

3 . The system of claim 1 , wherein the system comprises at least 2 first negative ion-based neutral beam injectors configured to introduce the high energy neutral atoms into the plasma in the first toroidal direction.

4 . The system of claim 1 , wherein the system further comprises at least one transfer system in communication with the first volume.

5 . The system of claim 4 , wherein the system comprises at least two transfer systems, wherein a first of the at least two transfer systems is in communication with the first volume, and wherein a second of the at least two transfer systems is in communication with the second volume.

6 . The system of claim 1 , wherein the electron heater is communicatively coupled to a controller.

7 . A system for generating neutrons comprising: (i) a casing defining a first volume; (ii) a blanket defining a second volume; (iii) a stellarator adapted to confine a plasma within the first volume, and wherein the blanket is positioned between the stellarator and the casing; (iv) at least a first negative ion-based neutral beam injector for introducing high energy neutral atoms into the plasma in a first toroidal direction; and (v) an electron heater adapted to heat electrons in the plasma; wherein the stellarator comprises (a) a plurality of planar shaping coils, wherein an array comprising the plurality of planar shaping coils encircles the plasma axis, but where any individual planar shaping coil of the plurality of planar shaping coils does not encircle the plasma axis; and (b) a plurality of planar encircling coils, wherein each individual planar encircling coil of the plurality of encircling coils encircles the plasma axis; and wherein any planar shaping coil of the plurality of planar shaping coils does not interlock with any planar encircling coil of the plurality of planar encircling coils.

8 . The system of claim 7 , wherein the system comprises at least 2 first negative ion-based neutral beam injectors for introducing the high energy neutral atoms into the plasma.

9 . The system of claim 7 , wherein the system further comprises at least one material transfer system.

10 . The system of claim 9 , wherein a first of the at least one material transfer system is in communication with the first volume.

11 . The system of claim 10 , wherein the first of the at least one material transfer system is communicatively coupled to a material isolation system.

12 . The system of claim 10 , wherein a second of the at least one material transfer system is in communication with the second volume.

13 . The system of claim 12 , wherein the second of the at least one material transfer system is communicatively coupled to a material isolation system.

14 . The system of claim 7 , wherein the electron heater is communicatively coupled to a controller.

15 . A system comprising: (a) a stellarator adapted to confine a plasma within a first volume, wherein the stellarator includes (i) a casing defining the first volume; and (ii) a blanket defining a second volume, the blanket enveloping the casing; (b) at least a first negative ion-based neutral beam injector for introducing high energy neutral atoms into the plasma in a first toroidal direction; (c) at least a second negative ion-based neutral beam injector for introducing high energy neutral atoms into the plasma in a second toroidal direction, wherein the first and second toroidal directions are opposite toroidal directions; and (d) an electron heater adapted to heat electrons in the plasma; wherein the stellarator comprises (i) a field-shaping coil system, wherein each field shaping unit comprises: one or more structural mounting elements; and one or more planar shaping coils disposed on a surface of the one or more structural mounting elements, wherein the one or more planar shaping coils do not interlock with each other, and where each of the one or more shaping coils do not individually encircle the plasma; and (b) a plurality of planar encircling coils which encircle the field-shaping coil system, and wherein each planar encircling coil of the plurality of planar encircling coils do not interlock with each other, and wherein any planar shaping coil of the plurality of planar shaping coils does not interlock with any planar encircling coil of the plurality of planar encircling coils.

Assignments (2)
CONFIRMATORY LICENSE Recorded Aug 8, 2023
From: PRINCETON UNIVERSITY
To: U.S. DEPARTMENT OF ENERGY
Reel/Frame 064531/0465 →
CONFIRMATORY LICENSE Recorded Jun 21, 2023
From: PRINCETON UNIVERSITY
To: UNITED STATES DEPARTMENT OF ENERGY
Reel/Frame 064045/0097 →
Continuity (2)
Provisional Application 63319588 · Mar 14, 2022
Related Publication 20230317304A1 · Oct 5, 2023
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